The invention relates to the treatment of effluent from a septic tank and, more particularly, to the treatment of effluent from the septic tank in a large holding tank having a second smaller tank therein under aerobic conditions which is then discharged into a disposal field.
Septic tank systems using the anaerobic method are widely used in disposing of sewage material from buildings and homes. Generally, the septic system includes a septic tank from which the effluent flows into a disposal field. In some cases, a pump in a pump tank is used to lift the effluent from the septic tank to the disposal field which can be in a higher elevation from the septic tank.
These septic tank systems collect all of the wastewater sewage from the building or home and treat the sewage material in the anaerobic environment. While the septic tank generally retains most of the organic solids therein which gravitate to the bottom of the tank, the liquid effluent flows out of the tank to the disposal field where it is intended to percolate downwardly into the surrounding soil. However, varying amounts of organic particles remain in the anaerobic treated liquid effluent flowing from the septic tank. Anaerobic bacteria feed on the organic particles which produces and becomes part of a slimy mass which then coats and adheres to all surfaces with which it comes in contact. This becomes a serious problem in the septic tank system disposal fields wherein the slime coats and adheres to the soil surrounding the disposal field thereby clogging the soil pores and considerably reducing the permeability of the soil. Frequently, the permeability of the surrounding soil is so reduced that the clogged disposal field fails completely causing the liquid effluent to percolate upwardly thereby completely saturating the entire surface and especially the top surface of the disposal field resulting in an environmentally disastrous condition. This condition is prevalent with a large number of septic tank systems and must be corrected at considerable labor and expense in many cases. However, it is particularly a serious problem with small size septic tank systems where there is a limited sized disposal field area available for use for reworking, and/or there are limited financial means available to be continuously faced with the problem.
It is known that sliming in the disposal field is greatly reduced in an aerobic environment thereby providing a longer life for the disposal field. Much of the previous improvements have been directed to modifying large septic tank systems which are designed generally for municipal treatment plants to provide for higher and more complex flows of effluent solids and liquid with expensive apparatus. Very few of the improvements are applicable to improving smaller systems by means of a simple and inexpensive method and apparatus. The present invention is directed to a simple and inexpensive method and apparatus for aeration of septic tank effluent which is applicable to small septic tank systems.